Semiconductor IC device fabricating method

Abstract

Either a chemical amplification positive electron beam resist film or a chemical amplification negative electron beam resist film is used selectively according to an IC fabricating process when forming a minute IC pattern by using, as a mask, a resist pattern formed by irradiating the chemical amplification electron beam resist film formed on a semiconductor wafer with an electron beam, to form the minute IC pattern quickly in a high accuracy and to carry out an electron beam direct writing at a high throughput. The chemical amplification electron beam resist film is coated with a conductive polymer film before irradiating the same with the electron beam to prevent the charging-up of the chemical amplification electron beam resist film and to stabilize the chemical amplification electron beam resist film during a electron beam writing process.

I claim: 
     
       1. A process of forming patterns overlying a major surface of a plate member using a resist pattern as an etching mask, the resist pattern being formed by irradiating a chemical amplification electron beam resist film, overlying the major surface of the plate member, with at least one electron beam, comprising: (a) forming a chemical amplification electron beam resist film over a first film, and coating a protective polymer film over the resist film;   (b) irradiating the resist film and protective polymer film with the at least one electron beam, forming an irradiated protective polymer film;   (c) removing the irradiated protective polymer film;   (d) after removing the irradiated protective polymer film, baking the resist film to promote a resist dissolving reaction using, as a catalyst, an acid produced in the resist film by irradiating the resist film with the at least one electron beam;   (e) developing the resist film to form the resist pattern; and   (f) etching the first film by using the resist pattern as a mask to form the patterns.   
     
     
       2. A process of forming patterns as recited in claim 1, wherein said patterns are opening patterns. 
     
     
       3. A process of forming patterns as recited in claim 1, wherein said patterns are thin film patterns. 
     
     
       4. A process of forming patterns as recited in claim 1, wherein the resist film is a positive resist film. 
     
     
       5. A process of forming patterns as recited in claim 4, wherein the patterns are opening patterns in the first film. 
     
     
       6. A process of forming patterns overlying a major surface of a plate member using a resist pattern as an etching mask, the resist pattern being formed by irradiating a chemical amplification electron beam resist film, overlying the major surface of the plate member, with at least one electron beam, comprising: (a) forming a chemical amplification electron beam resist film over a first film, and coating a protective polymer film on the resist film;   (b) irradiating the resist film and the protective polymer film with the at least one electron beam, forming an irradiated protective polymer film;   (c) removing the irradiated protective polymer film;   (d) after removing the irradiated protective polymer film, baking the resist film to promote a resist dissolving reaction using, as a catalyst, an acid produced in the resist film by irradiating the resist film with the at least one electron beam;   (e) developing the resist film to form the resist pattern; and   (f) etching the first film by using the resist pattern as a mask to form the patterns.   
     
     
       7. A process of forming patterns as recited in claim 6, wherein said patterns are opening patterns. 
     
     
       8. A process of forming patterns as recited in claim 6, wherein said patterns are thin film patterns. 
     
     
       9. A process of forming patterns as recited in claim 6, wherein the protective film is formed directly on the resist film. 
     
     
       10. A process of forming patterns as recited in claim 9, wherein the resist film is a positive resist film. 
     
     
       11. A process of forming patterns as recited in claim 10, wherein the patterns are opening patterns in the first film. 
     
     
       12. A process of forming patterns overlying a major surface of a plate member using a resist pattern as an etching mask, the resist pattern being formed by irradiating a chemical amplification electron beam resist film, overlying the major surface of the plate member, with at least one electron beam, comprising: (a) forming a chemical amplification electron beam resist film over a first film, and coating a protective polymer film over the resist film;   (b) irradiating the resist film and the protective polymer film with the at least one electron beam, forming an irradiated protective polymer film;   (c) removing the irradiated protective polymer film;   (d) after removing the irradiated protective polymer film, baking the resist film;   (e) developing the resist film to form the resist pattern; and   (f) etching the first film by using the resist pattern as a mask to form the patterns.   
     
     
       13. A process of forming patterns as recited in claim 12, wherein said patterns are opening patterns. 
     
     
       14. A process of forming patterns as recited in claim 12, wherein said patterns are thin film patterns. 
     
     
       15. A process of forming patterns as recited in claim 12, wherein the resist film is a positive resist film. 
     
     
       16. A process of forming patterns as recited in claim 15, wherein the patterns are opening patterns in the first film. 
     
     
       17. A process of forming patterns overlying a major surface of a plate member using a resist pattern as an etching mask, the resist pattern being formed by irradiating a chemical amplification electron beam resist film, overlying the major surface of the plate member, with at least one electron beam, comprising: (a) forming a chemical amplification electron beam resist film over a first film, and coating a protective polymer film on the resist film;   (b) irradiating the resist film and the protective polymer film with the at least one electron beam, forming an irradiated protective polymer film;   (c) removing the irradiated protective polymer film;   (d) after removing the irradiated protective polymer film, baking the resist film;   (e) developing the resist film to form the resist pattern; and   (f) etching the first film by using the resist pattern as a mask to form the patterns.   
     
     
       18. A process of forming patterns as recited in claim 17, wherein said patterns are opening patterns. 
     
     
       19. A process of forming patterns as recited in claim 17, wherein said patterns are thin film patterns. 
     
     
       20. A process of forming patterns as recited in claim 17, wherein the protective polymer film is formed directly on the resist film. 
     
     
       21. A process of forming patterns as recited in claim 20, wherein the resist film is a positive resist film. 
     
     
       22. A process of forming patterns as recited in claim 21, wherein the patterns are opening patterns in the first film.